During surgery, it is now common for surgeons to wear a head-mounted video camera positioned in front of the forehead of the surgeon. Such a camera is preferably positioned to image the surgical field. The provision of the camera has a number of advantages. Firstly, it allows others in the surgical team to follow the progress of the surgery on a video screen rather than having to crowd closely about the surgeon to obtain a clear view of the surgical site. This can be particularly advantageous where the surgery is being performed on the small body of a child. By being able to follow the surgery on a video screen, surgical assistants and theatre staff can also be aware of when they are required to take action without crowding the surgeon or blocking the illuminated surgical area.
Recordal of the surgery is also useful if the surgeon wishes to retain a record of the surgical procedure. Video records of such surgery can be particularly useful as an educational tool and for providing an unambiguous record of the actions taken by the surgeon.
One disadvantage of video recordal is the weight and bulkiness of the camera that must be worn by the surgeon. Given that many surgical procedures can last many hours, the necessity of carrying a relatively heavy camera on the forehead can lead to fatigue and neck and back strain for the surgeon. The position of the camera on the forehead also serves to provide a video image that is offset from the actual field of view of the surgeon. This can occasionally result in the camera not being able to image the actual surgical site being operated upon by the surgeon. This is typically compensated by use of a camera with a wide field of view. This in turn, however, has the disadvantage that fine detail in the imaged view of the surgery is lost.
The present invention is directed to an optical system adapted to address some of the problems of existing systems.
Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention before the priority date of each claim of this application.